/*
 * Copyright (c) 2019, 2021 Oracle and/or its affiliates.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package io.helidon.common.reactive;

/**
 * A collector accumulates the items provided when {@link #collect(java.lang.Object)} is invoked and makes them available in a
 * single container object with {@link #value()}.
 *
 * @param <T> collected items type (input)
 * @param <U> result container type (output)
 */
public interface Collector<T, U> {

    /**
     * Collect the given item.
     *
     * @param item item to collect
     */
    void collect(T item);

    /**
     * Get the collected items container.
     *
     * @return U
     */
    U value();
}
